This is a divisional of application Ser. No. 08/086,192 filed on Jun. 30, 1993, U.S. Pat. No. 5,345,648, which is a continuation of Ser. No. 07/800,430 filed Nov. 29, 1991, now abandoned.
FIELD OF THE INVENTION
The present invention relates generally to a paint roller frame and cage assembly which securely fastens a roller cover to the frame while painting and still allows the roller cover to be quickly and easily removed therefrom for ease of cleaning of the cage assembly and replacement of the roller cover after use.
BACKGROUND OF THE INVENTION
There are many different types of paint roller frames and cage assemblies that permit the removal and replacement of paint roller covers with varying degrees of difficulty. However, one of the major drawbacks of most paint roller frames and cage assemblies of this type is that if the roller cover is relatively easy to insert and remove, it is usually not as positively and securely retained in place during use as one would like, and vice versa. Another drawback is that some cage assemblies used to support the paint roller cover during painting include substantial areas where paint may become entrapped, making such cage assemblies difficult to clean. Also, most cage assemblies of this type do not provide uniform full-span support of the roller cover, whereby the roller cover may develop flat spots or become out of round, making it much less effective in spreading paint.
SUMMARY OF THE INVENTION
The present invention provides a paint roller frame and cage assembly that allows for the easy assembly and removal of a roller cover from the cage assembly and yet positively and securely retains the roller cover in place on the cage assembly during use.
In accordance with one aspect of the invention, a retaining spring located adjacent the inboard end of the cage assembly is used to securely fasten the roller cover to the cage assembly while painting and still allow the roller cover to be quickly and easily removed after use for ease of cleaning and/or replacement.
In accordance with another aspect of the invention, the retaining spring includes a Belleville type spring washer portion and a plurality of circumferentially spaced apart spring fingers extending radially and axially outwardly from the outer periphery of the washer portion. The deflection of the Belleville type spring washer portion permits the finger length to be relatively short to minimize possible areas of entrapment of paint both under the fingers and inside the associated supporting structure and still achieve the necessary overall deflection of the fingers to retain the normal range of tolerances of roller covers on the cage assembly.
In accordance with yet another aspect of the invention, the cage assembly provides uniform support of the roller cover throughout substantially its entire length, preventing the roller cover from developing flat spots or becoming out of round during use.
Further in accordance with this invention, the cage assembly is relatively lightweight for reduced fatigue.
In accordance with another aspect of the invention, the cage assembly is easy to clean when the roller cover is removed therefrom.
These and other objects, advantages, features and aspects of the present invention will become apparent as the following description proceeds.
To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail a certain illustrative embodiment of the invention, this being indicative, however, of but one of the various ways in which the principles of the invention may be employed.
BRIEF DESCRIPTION OF THE DRAWINGS
In the annexed drawings:
FIG. 1 is a perspective view of a preferred form of roller frame and cage assembly in accordance with this invention;
FIG. 2 is an enlarged perspective view of the retaining spring of FIG. 1 which is used to securely fasten a roller cover to the cage assembly;
FIG. 3 is an enlarged fragmentary longitudinal section through the roller frame and cage assembly of FIG. 1 showing a roller cover securely fastened to the cage assembly by a retaining spring adjacent the inboard end of the cage assembly;
FIG. 4 is an enlarged transverse section through the roller frame and cage assembly of FIG. 3, taken generally along the plane of the
line 4--4 thereof;
FIG. 5 is a further enlarged fragmentary longitudinal section through the inboard end of the roller frame and cage assembly of FIG. 3, but showing the Belleville type spring washer and associated fingers of the retaining spring in the relaxed position prior to insertion of a roller cover over the spring fingers; and
FIG. 6 is an enlarged fragmentary longitudinal section through the inboard end of the roller frame and cage assembly, similar to FIG. 5, but showing the Belleville type spring washer and associated fingers of the retaining spring in the tensioned position frictionally retaining a roller cover in place on the cage assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now in detail to the drawings, and initially to FIGS. 1, 3 and 4, there is shown a preferred form of paint roller frame 1 and
cage assembly 2 in accordance with this invention. The frame 1 is made from a heavy gauge wire or rod bent to shape to provide a handle portion 3 at one end and a
shaft portion 4 at the other end for rotatably supporting the
cage assembly 2 thereon. Attached to the handle portion 3 is a hand grip 5 (see FIG. 1) to facilitate grasping of the paint roller frame with one hand. A threaded socket (not shown) may be provided in the outer end of the
hand grip 5 to permit attachment of an extension pole, if desired.
The
cage assembly 2 includes a substantially rigid one
piece cage body 8 preferably made of injection molded, fiberglass-filled nylon for increased strength and durability. The
cage body 8 comprises a plurality of circumferentially spaced, longitudinally extending roller
cover support bars 9 joined together at a plurality of axially spaced locations by
arcuate ribs 10 extending between the bars. Preferably the height of the
ribs 10 substantially corresponds to the height of the
bars 9, and where joined to the bars, form axially spaced
annular rings 11 each having an outer diameter slightly less than the inner diameter of a
paint roller cover 12 to be supported thereby.
Although the number and spacing of the
support bars 9 and
support rings 11 may vary, in the preferred embodiment disclosed herein, four such support bars are provided, each spaced approximately 90° apart. Also, such bars are connected together at their ends and at three uniformly spaced apart places intermediate their ends by the aforementioned rib-
like members 10 which form five such support rings
At the outboard end of the
cage body 8 is an integrally molded
central hub portion 15 having an axial opening 16 therethrough in which is press fitted a
bushing 17 for rotatably receiving the shaft portion 4 (see FIG. 3). The
cage body 8 is otherwise substantially open throughout its length except for a pair of relatively short
annular flanges 19, 20 at opposite ends thereof on which closed
end caps 21, 22 are mounted to prevent paint from getting inside the roller cover. Leaving the
cage body 8 substantially open reduces the overall weight of the
cage assembly 2 for reduced fatigue and makes it easy to clean when the
roller cover 12 is removed therefrom.
The
inboard end cap 21 includes three coaxially extending, radially spaced
annular sleeve portions 23, 24 and 25 (see FIGS. 5 and 6). The radial
innermost sleeve 23 includes an axial opening 26 therethrough in which an
inboard bushing 27 may be press fitted also for rotatably receiving the
shaft portion 4. Both
bushings 17 and 27 may be made of silicon impregnated Delrin for reduced friction with the
shaft 4. At the outer end of the
inner sleeve 23 is a
counterbore 28 for receipt of a
flange 29 on the end of bushing 27.
The
intermediate sleeve 24 is radially outwardly spaced from the
inner sleeve 23 to provide an
annular recess 30 therebetween for receipt of the
annular flange 19 on the inboard end of the
cage body 8. The inner diameter of
flange 19 desirably forms a continuation of the annulus defined by the radial inner edges of the
support bars 9 and interconnecting
ribs 10. The outer diameter of
flange 19, on the other hand, is less than the annulus defined by the radial outer edges of the
bars 9 and interconnecting
ribs 10 for telescoping receipt of the
intermediate sleeve 24 over the
flange 19 while still providing a radial clearance between the outer diameter of the
intermediate sleeve 24 and annulus formed by the radial outer edges of the
support bars 9 and interconnecting
ribs 10 for a purpose to be subsequently described.
To secure the
inboard end cap 21 to the
cage body 8, an
annular rib 31 is provided on the inner diameter of the
intermediate sleeve 24 for snapping engagement into an
annular groove 32 on the outer diameter of
flange 19 to provide a snap lock between the
end cap 21 and
flange 19. When thus assembled, the outer diameter of the
outer sleeve 25 substantially corresponds to the annulus defined by the radial outer edges of the
support bars 9 and interconnecting
ribs 10 to provide a continuation of such surface for supporting a
roller cover 12 thereon. Extending radially outwardly beyond the inboardmost end of the
outer sleeve 25 is an
annular shoulder 33 which acts as a stop for locating the
roller cover 12 on the
cage assembly 2 when fully inserted thereon.
To securely fasten the
roller cover 12 to the
cage assembly 2 while painting, a
retaining spring 40 preferably made of cadmium-plated spring steel is mounted on the inboard end of the cage assembly. As best seen in FIGS. 2, 5 and 6, the
retaining spring 40 includes a Belleville type
spring washer portion 41 having an inner diameter slightly greater than the outer diameter of the
inboard end flange 19 for sliding receipt thereon and trapping of the washer between the inboard ends of the
support bars 9 and adjacent end of the
intermediate sleeve 24. The outer diameter of the
washer 41 is slightly less than the annulus formed by the radial outer edges of the
support bars 9 and interconnecting
ribs 10. Also, the axial length of the
outer sleeve 25 is slightly less than that of the
intermediate sleeve 24 to provide an
annular recess 42 between the inboard ends of the support bars and adjacent end of the
outer sleeve 25 for receipt of a plurality of circumferentially spaced
fingers 43 extending radially and axially outwardly from the outer diameter of the
washer 41 in the direction of the inboard end of the cage assembly.
When the retaining
spring 40 is in the relaxed position shown in FIG. 5 with the
roller cover 12 out of engagement with the
fingers 43, the fingers extend radially outwardly beyond the normal range of inner diameter tolerances of roller covers to be used with the frame and cage assembly. For example, the normal range of tolerances of the inner diameters of the roller covers may be between approximately 1.47 inches and 1.5 inches, in which event the maximum outer diameter of the
fingers 43 in the relaxed position may be on the order of 1.6 inches. Also, the
fingers 43 gradually taper radially outwardly from the outer diameter of the
washer 41 to the maximum diameter of the
fingers 43 to facilitate wedging of the
roller cover 12 over the fingers when the roller cover is pushed all the way up against the
shoulder 33 on the
inboard end cap 21 as shown in FIGS. 3 and 6. During axial movement of the
roller cover 12 over the
fingers 43, the fingers are tensioned radially inwardly into the
annular space 42 between the inboard ends of the
support bars 9 and adjacent end of the
outer sleeve 25.
To permit the finger length to be as short as possible to minimize possible areas of entrapment of paint both under the-
fingers 43 and inside the
inboard end cap 21 and still achieve the necessary overall deflection of the fingers to accommodate the normal range of tolerances of roller covers 12, the majority of the deflection of the fingers, for example, approximately 90% of such deflection, is desirably accommodated for by the deflection of the Belleville type
spring washer portion 41 from the FIG. 5 position to the FIG. 6 position. Only a small portion of the total deflection of the fingers, for example, approximately 10%, is desirably accommodated for by the actual deflection of the fingers themselves.
In the preferred embodiment disclosed herein, the
fingers 43 have an overall length of approximately 0.4 inch. Yet the total deflection of the fingers including the deflection resulting from the deflection of the
spring washer portion 41 during insertion of the
roller cover 12 over the fingers is approximately 0.06 inch.
When the
fingers 43 are in the tensioned position shown in FIG. 6, the fingers preferably engage the inner diameter of the
roller cover 12 over only approximately one-third of their length. Also, the outermost ends 44 of the
fingers 43 taper slightly radially and axially inwardly away from the inner diameter of the
roller cover 12 to prevent the ends of the fingers from digging into the roller cover during removal of the roller cover from the cage assembly. The total tension force exerted by the retaining
spring 40 against the inner diameter of the roller cover is sufficient to securely fasten the roller cover to the
cage assembly 2 while painting. Yet removal of the roller cover is easily accomplished with a single pull of the roller cover or a gentle tap of the roller frame 1 on the edge of a large sized paint can. Moreover, since the normal tolerance variations of the roller covers 12 used with the roller frame and cage assembly of the present invention are relatively small in comparison to the overall deflection of the
fingers 43, the tension force exerted by the retaining
spring 40 on such roller covers is substantially uniform.
The
cage assembly 2 is retained against axial movement on the
shaft 4 as by staking the shaft adjacent the inboard end of the
cage assembly 2 at 45 and roll forming the
outermost end 46 of the shaft after the
cage assembly 2 has been inserted onto the shaft. Also,
washers 47 may be inserted between the
stakes 45 and roll formed
end 46 of the
shaft 4 and adjacent ends of the
bushings 17, 27 to reduce friction.
After the
cage assembly 2 has been assembled onto the
shaft 4, the
outboard end cap 22 is fitted over the outboard end of the
cage body 8 as shown in FIG. 3 to prevent paint from getting inside the roller cover through such end. To secure the
end cap 22 in place, an
annular groove 48 may be provided in the outer diameter of the
flange portion 20 for snapping receipt of an
inturned lip 49 on the
cylindrical wall 50 of the end cap to provide a snap lock between the
end cap 22 and
flange portion 20. Also, the outer end of the
flange 20 may be tapered radially inwardly toward its outermost end to facilitate wedging of the
inturned lip 49 on the
end cap 22 up over the
flange 20 and into the
groove 48. The outer diameter of the
outboard end cap 22 substantially corresponds to the outer diameter of the annulus formed by the radial outer edges of the support bars 9 and interconnecting
ribs 10 to provide a smooth uninterrupted surface for supporting the
roller cover 12 on the cage assembly. Also, there is virtually no gap between the outboard ends of the support bars 9 and adjacent end of the
outboard end cap 22 where paint could accumulate.
In the preferred embodiment disclosed herein, each
support bar 9 is approximately 7.7 inches long, 0.1 inch thick, and 0.3 inch high. The
flange portion 20 at the outboard end of the
cage assembly 2 has an axial length of approximately 0.3 inch, and the
surrounding end cap 22 has an overall length of approximately 0.5 inch. The
flange portion 19 at the inboard end of the cage assembly has an axial length of approximately 0.5 inch and the
surrounding end cap 21 has an overall length of approximately 0.8 inch. Also, the
cage assembly 2 has an overall length from the outer end of the
end cap 22 up to the
shoulder 33 on the
end cap 21 of approximately 9 to 9.1 inches to provide substantially uniform support for a 9 inch roller cover substantially throughout its entire length, preventing the roller cover from developing flat spots or becoming out of round during use. The
annular recess 42 between the inboard ends of the support bars 9 and adjacent end of the
outer sleeve 25 of the
inboard end cap 21 in which the retaining
spring fingers 43 are received has a length of approximately 0.4 to 0.5 inch.
Although the invention has been shown and described with respect to a certain preferred embodiment, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of the specification. The present invention includes all such equivalent alterations and modifications, and is limited only by the scope of the claims.